The index is designed to minimize the interest-rate risk exposure of a portfolio composed of U.S. dollar-denominated, investment grade bonds, represented in the index by the underlying fund, by including a series of up to 10 interest rate swap contracts with different maturities. The fund invests, under normal circumstances, at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in component securities and instruments in the index and/or bonds included in the underlying index of the underlying fund.